Thermal cut-out.



No. 757,884.. PATENTED APR. 19, 1904. H. P. CLAUSEN,

THERMAL GUT-OUT.

APPLICATION FILED JULY 1a, 1903.

No MODEL.

z//Mf/ l f .nimma NTTnD' STATES 'Patented April 19,1904.

PATENT `-i rrrca.

HENRY P. CLAUSEN,-OF CHICAGO, ILLINOIS, ASSIGNOR TO P. C. BURNS AND J.G. IHMSEN, OF CHICAGO, ILLINOIS.

CUT-OUT.

SPECIFICATION forming part of Letters Patent No. 757,884, dated April19, 1904.

Application filed .Tuly 18, 1903.

To all 1li/7,0717. it 717/04/ cfm/cern:

Be it known that I, 'HENRY P. CLAUsnN, a citizen of the United States ofAmerica, and a resident of Chicago, Cook county, Illinois, have inventeda certain new and useful Improvement inThermal Cut-Outs, of which thefollowing is a specification. y

My invention relates to a type of thermal cut-out in which a mass ofsolder or other fusible material is employed for keepingthe circuitnormally closed and in which a coil of wire or other suitable heatconcentrating member is arranged to melt or fuse the said solder orother fusible material upon the passage of an abnormally strong current,it being also usually desirable to provide means for connecting theline-circuit with ground simultaneously with the opening of suchcircuit.

Generally stated, the object of my invention is to provide an improvedand highly efficient thermal cut-out of the foregoing character.

A special object is to provide a construction I and arrangement wherebythe solder or other fusible material will be subjected to a shearingaction when it softens or partially melts, so as to render the cut-outmore responsive and quicker in action. Prior to my inventionthermalcut-outs have usually been constructed in such manner that it wasusually necessary to mash or flatten the entire mass of solder, severthe mass of solder by a direct or tensile strain, or to break theconnection in some similar way, and in each case it is obvious that acomplete melting down or softening of the ysolder is necessary. With myimproved arrangement, however, in which a thin sheet of solder isinterposed between two sharp-edged members which tend normally toproduce a shearing action and which then do effect a shearing action assoon as the sheet of solder becomes slightly softened or partiallymelted, it will be readily seen that a much quicker and more responsivedevice is provided and that as a consequence the circuit is openedbefore the trespassing current can do any harm.

To the foregoing and other useful ends my invention consists in mattershereinafter set forth and claimed.

In the accompanying drawings, Figure 1 is Serial No. 166,198. (Nomodel.)

an enlarged longitudinal section of an improved heat-coil whichconstitutes a part of my improved thermal cut-out. Fig. 2 is an yend,elevation of the heat-coil shown in Fig. l. Fig. 3 is a view of theother end of said heatcoil. Fig. 4 is a view, partly in section andpartly in side elevation, of my improved thermalv cut-out with the saidheat-coil mounted in place and ready for action.

As thus illustrated my improved thermal cut-out comprises a suitablebase A, a post B anda spring C, mounted on said base and insulatedtherefrom, and a couple of insulated contacts D and E. The contact D canbe mounted on the post B, Aas shown, while the sulated from the springC. rlhe contact E, however, normally engages the spring C. The heat-coilF, to which my invention more particularly relates, is preferably formedwith a spool-shaped head f, adapted to engage the notched upper end ofthe spring' l, and with a pin f', adapted to project through an openingin the post B. rlhe sleeve f2 constitutes a shoulder adapted to bearagainst the post B forthe purpose of normally preventing the spring Cfrom forcing the end of the pin'f' into engagement with thecontact-spring l).

The internal construction of the heat-coil, as shown in Fig. l,comprises a framef, which is rigid with the pin f' and also electricallyconnected therewith, but which is insulated from the head f by means ofa hub-like piece of insulation f4. A heating-coil'or coil of highresistance f5 encircles the said frame f3, one terminal, f, of thisheat-coil being' preferably soldered to the head f and the otherterminal, f7, being preferably soldered to the frame f3. A telescopingmember f3 is slidingly mounted on the pin f and ispreferabl y providedwith a hub-like piece of insulation f. The sleeve f2, previouslyreferred to, is preferably rigid or integral with the said slidingmember f8. The. frame f3 and mally prevented from telescoping one withina the other by an interposed sheet of solder or other suitable fusiblematerial 1. This sheet of solder can, if desired, be in the form ofaflat ring adapted to fit upon the hub f" of insulacontact E can bemounted on the base and in-V the telescoping or sliding member f S arenor- IOO tion. lhen the heat-coil is adjusted in place, the opposingedges of the cylindric frame f and the slidingl member f normallysubject the sheet ol" solder .fw to a shearing pressure or actionthat isto say, the pressure oit the spring (l tends normally to exert ashearing' pressure or action on the `said solder. Such being the case itwill be seen that when a trespassin g or abnormally stron g current traverses the circuit, thereby passing from the post B, through the pin j,thence through the 'trame fi to the heat-coil f, thence throughthemetallic head j and the spring C, this normal tendency to produce ashearing action is then developed into a positive or actual shearing ot'the solder, for the heat generated by the heat-coil will be sui'licientto soften or partially melt the solder, and the pressure of the spring Cis then suilicient to cause the telescoping members f and fs totelescope one within the other, thereby shearing or cutting the sheet orring-like piece of solder in two. The smaller or inner ring portion ot'the solder will be carried forward by the member fx, while the outer orlarger ring portion of the solder will be pushed outward and will Vtalldown upon and encircle the sleeve f2.

Thus it will be seen that a very thin sheet ol solder can be employed asa means t'or holding the parts in their normal positions and thatconsequently a quick and eli'ective shearing' action is produced as soonas the solder softens or partially melts, with the result that thedevice as a whole is of a very responsive and eiiicient character. Thereis absolutely nodanger ot' the melted solder impeding or interferingwith the desired movement ot' the parts t'or the purpose of opening thecircuit.

lV hat I claim as my invention is- 1. A thermal eut-out comprising aheat-concentrating member, softenable material associated with saidmember and adapted to be softened by the heat thereof, coacting membersbearing upon opposite sides ot' said sot'- tenable material, and meansincluding' a spring For causing the said coacting members to .shear theso'lftenable material upon the pas- 3. A thermal eut-out comprising aheat-concentrating member, a body ot solj'tenable material, and meansincluding' relatively sliding members and a spring for shearing saidmaterial upon the passage of an abnormally strong' current and theconsequent softening of said material, the said soltenable materialbeing removably interposed between the opposing edges ot' said members.

4. A thermal cut-out comprising a suitable heating-miba thin sheet olsottenable material, and means including a pair ol sharpedgedtelescoping members and a spring Afor shearing' said sheet oit'softenable material upon the passage of an abnormally strong' currentand the consequent softening olI said material, said softenable materialbeing interposed between the opposing' ends of said members.

A thermal cut-out comprising means for maintaining the electricalcontinuity ol,E a circuit and for opening' said circuit upon the passageof an abnormally strong current, said means including' a heat-coil and asuitable spring, and including' also a small thin removable ring ofsolder positioned in place to normally hold said spring under tension,but adapted when so'ltened by the heat oli said coil to release saidspring'.

6. A thermal cut-out comprising a member, so'l'tenable material engagingsaid member, a shearing member having a cutting' edge bearing normallyagainst said sottenable material, a high resistance associated with saidsottenable material, and a spring normally exertingr its tension throughsaid shearing member on the sottenable material.

7. A thermal protector comprising a support, a thin ring' ol solder onsaid support, a

shearing' member adapted to telescope over said support and providedwith a circular cutting edge bearing normally against said solder, aheating,l member associated with said solder, and a spring normallyexerting its tension through said shearing' member on the solder.

A thermal cut-out, comprising a body ol softenable material, a pair ot'shearingr members held normally against relative movement by saidmaterial, a resistance associated with said material, and a spring'acting to shear said material upon the passage ol sullicient currentthrough said resistance and the con sequent softening ot' said material.

Signed by me at Chicago, (look coi'mty, l llinois, this 9th day ot July,1903.

HENRY l?. CLAUSEN.

lVitnesses:

l). R.. HormIAN, M. TiIoMAs.

